1. Field of the Invention
This invention relates to cis-platinum (II) complexes of isomers(cis-, trans-d- and trans-l-isomers) of 1,2-diaminocyclohexane. More particularly, it relates to cis-platinum (II) complexes of isomers (cis-, trans-d-, and trans-l-isomers) of 1,2-diaminocyclohexane represented by the general formula ##STR3## wherein the stereoisomerism of 1,2-diaminocyclohexane is cis-, trans-d-, or trans-l-; and R.sup.1 and R.sup.2 represent same halogen atoms, or R.sup.1 and R.sup.2 may, when taken together, form a group represented by the formula ##STR4## where R.sup.3 represents a &gt;CH.sub.2 group, a &gt;CHCH.sub.3 or &gt;CHCH.sub.2 CH.sub.3 group. Further it relates to complexes of uracil and cis[platinum(II)-cis, trans-d-, or trans-l-1,2-diaminocyclohexane] (hereinafter referred to as "cis-uracil(cis-, trans-d- or trans-l-1,2-diaminocyclohexane) platinum(II) complex")
2. Description of the Prior Art
1,2-Diaminocyclohexane platinum (II) complexes have hitherto been known as compounds having an anti-tumor activity.
Synthesis method and anti-tumor activity of 1,2-Diaminocyclohexane platinum (II) complexes are disclosed in "Chem.-Biol. Interaction", vol. 5, 415-424 (1972) by Connors, T. A. et.al., "Bioinorg. Chem." Vol. 2, 187-210 (1973) by Clearo, M. J. et.al and "Res. Commun. Chem. Pathol. Pharmacol." Vol. 7, 529-538 (1974) by Gale, G. R. et.al.
Since the starting material of the above platinum (II) complex, 1,2-diaminocyclohexane (hereinafter referred to as "1,2-DAC" for brevity) has been available as a mixture of cis-, trans-d- and trans-l-isomers thereof, the corresponding platinum (II) complex derived from the starting material is a mixture of three isomers, i.e., a cis-isomer, a trans-d-isomer and a trans-l-isomer. The cis-isomer is a geometrical isomer and the trans-d- and trans-l-isomers are optical isomers.
It has been reported that 1,2-diaminocyclohexane platinum (II) complex has an anti-tumor activity. This activity of 1,2-diaminocyclohexane platinum (II) complex, however, has been confirmed using a mixture of two or more isomers thereof, and it has not been known which cis-platinum (II) complex of 1,2-DAC isomers exhibits sufficient anti-tumor activity and low toxicity.